Anti-IL-8 antibody activates myeloid cells and potentiates the anti-tumor activity of anti-PD-1 antibody in the humanized pancreatic cancer murine model.

Pancreatic ductal adenocarcinoma(PDAC) does not respond to single-agent immune checkpoint inhibitor therapy, including anti-PD-1 antibody(aPD-1) therapy. Higher plasma levels of IL-8 are associated with poorer outcomes in patients who receive aPD-1 therapies, providing a rationale for combination immunotherapy with an anti-IL-8 antibody(aIL-8) and aPD-1. We thus investigated whether human aIL-8 therapy can potentiate the antitumor activity of aPD-1 and further investigated how the combination affects the immune response by regulating myeloid cells in the tumor microenvironment in a humanized murine model of PDAC with a reconstituted immune system consisting of human T cells and a combination of CD14+ and CD16+ myeloid cells. The results show that the combination of aIL-8 and aPD-1 treatment significantly enhanced antitumor activity following the infusion of myeloid cells. Our results further showed that the target of IL-8 is mainly present in CD16+ myeloid cells and is likely to be granulocytes. FACS analysis showed that aIL-8 treatment increased granulocytic myeloid cells in tumors. Consistently, single-nuclear RNA-sequencing analysis of tumor tissue showed that the innate immune response and cytokine response pathways in the myeloid cell cluster were activated by aIL-8 treatment. This is the first preclinical study using a humanized mouse model for new combination immunotherapeutic development and supports the further clinical testing of aIL-8 in combination with aPD-1 for PDAC treatment. This study also suggests that peripherally derived myeloid cells can potentiate the antitumor response of T cells, likely through the innate immune response, and aIL-8 re-educates tumor-infiltrating myeloid cells by activating the innate immune response.

CCR2/CCR5 inhibitor permits the radiation-induced effector T cell infiltration in pancreatic adenocarcinoma.

The resistance of pancreatic ductal adenocarcinoma (PDAC) to immune checkpoint inhibitors (ICIs) is attributed to the immune-quiescent and -suppressive tumor microenvironment (TME). We recently found that CCR2 and CCR5 were induced in PDAC following treatment with anti-PD-1 antibody (αPD-1); thus, we examined PDAC vaccine or radiation therapy (RT) as T cell priming mechanisms together with BMS-687681, a dual antagonist of CCR2 and CCR5 (CCR2/5i), in combination with αPD-1 as new treatment strategies. Using PDAC mouse models, we demonstrated that RT followed by αPD-1 and prolonged treatment with CCR2/5i conferred better antitumor efficacy than other combination treatments tested. The combination of RT + αPD-1 + CCR2/5i enhanced intratumoral effector and memory T cell infiltration but suppressed regulatory T cell, M2-like tumor-associated macrophage, and myeloid-derived suppressive cell infiltration. RNA sequencing showed that CCR2/5i partially inhibited RT-induced TLR2/4 and RAGE signaling, leading to decreased expression of immunosuppressive cytokines including CCL2/CCL5, but increased expression of effector T cell chemokines such as CCL17/CCL22. This study thus supports the clinical development of CCR2/5i in combination with RT and ICIs for PDAC treatment.

Risk Factors Associated With Readmission After Pancreatectomy: A Single-Institution Retrospective Cohort Study.

BACKGROUND: Pancreatectomy has a significant rate of procedure-specific morbidity which can result in readmission. Readmission has been proposed as a measure of quality. The goal of this study is to determine what factors are associated with readmission after pancreatectomy and whether readmission can be prevented. METHODS: A retrospective review of a single institution's pancreatectomies between January 2011 and April 2015 was performed. Demographic, perioperative, and outpatient data were collected from the medical record. Primary outcome was 90-day readmission. Univariate and multivariable analyses were performed to determine which factors were associated with increased risk for readmission. RESULTS: A total of 257 patients met inclusion criteria; the 90-day readmission rate was 32.7%. The median time to readmission was 13 days. Readmitted patients were more likely to have a postoperative pancreatic fistula (POPF) on univariate analysis. Surgical site infections were more common in readmitted patients (18% vs 6.4%, P = .0138). Upon multivariable adjustment, only POPF (P = .0005) remained significant. A positive dose-response relationship was noted between POPF grade and the odds of readmission with odds ratios (ORs) ranging from 1.6 (95% Confidence Interval (CI): .6-4.1) for grade A to 16.7 (95% CI: 1.8-156.8) for grade C, albeit with limited precision. CONCLUSIONS: Readmission after pancreatectomy is a common occurrence despite the many advancements in perioperative care. Our data suggest that POPF is a risk factor for readmission after pancreatectomy. Presently, this factor is not clearly preventable. This suggests that readmission may not be the best measure of quality to utilize in the evaluation of pancreatic surgery.

CT Radiomics-Based Preoperative Survival Prediction in Patients With Pancreatic Ductal Adenocarcinoma.

OBJECTIVE. Pancreatic ductal adenocarcinoma (PDAC) is often a lethal malignancy with limited preoperative predictors of long-term survival. The purpose of this study was to evaluate the prognostic utility of preoperative CT radiomics features in predicting postoperative survival of patients with PDAC. MATERIALS AND METHODS. A total of 153 patients with surgically resected PDAC who underwent preoperative CT between 2011 and 2017 were retrospectively identified. Demographic, clinical, and survival information was collected from the medical records. Survival time after the surgical resection was used to stratify patients into a low-risk group (survival time > 3 years) and a high-risk group (survival time < 1 year). The 3D volume of the whole pancreatic tumor and background pancreas were manually segmented. A total of 478 radiomics features were extracted from tumors and 11 extra features were computed from pancreas boundaries. The 10 most relevant features were selected by feature reduction. Survival analysis was performed on the basis of clinical parameters both with and without the addition of the selected features. Survival status and time were estimated by a random survival forest algorithm. Concordance index (C-index) was used to evaluate performance of the survival prediction model. RESULTS. The mean age of patients with PDAC was 67 ± 11 (SD) years. The mean tumor size was 3.31 ± 2.55 cm. The 10 most relevant radiomics features showed 82.2% accuracy in the classification of high-risk versus low-risk groups. The C-index of survival prediction with clinical parameters alone was 0.6785. The addition of CT radiomics features improved the C-index to 0.7414. CONCLUSION. Addition of CT radiomics features to standard clinical factors improves survival prediction in patients with PDAC.

Autoimmune Pancreatitis: A Critical Analysis of the Surgical Experience in an Era of Modern Diagnostics.

OBJECTIVE: The aim of this study was to critically analyze the surgical experience of managing autoimmune pancreatitis (AIP) in an era of modern diagnostics and compare these patients with those who were managed conservatively. METHODS: Two prospectively maintained databases were used to retrospectively identify patients with AIP who were either managed conservatively or underwent pancreatectomy. RESULTS: Eighty-eight patients were included in the study, of which 56 (63.6%) underwent resection and 32 (36.4%) were managed conservatively. Patients who underwent resection were more likely to present with jaundice (64.3% vs 18.1%, P < 0.001) and weight loss (53.6% vs 15.6%, P = 0.005). The cohort who underwent resection had a significantly higher median carbohydrate antigen 19-9 (40.0 vs 18.6 U/mL, P = 0.034) and was less likely to have elevated immunoglobulin G4 (26.1% vs 50.0%, P < 0.001). The most frequent initial diagnosis in the cohort who underwent resection was ductal adenocarcinoma (82.1%). Nine patients (28.1%) in the conservatively managed cohort experienced AIP relapse compared with 6 patients (10.7%) in the cohort who underwent resection. CONCLUSIONS: The most frequent reason for surgical resection of AIP is concern for malignancy. Carbohydrate antigen 19-9 elevations were more common than immunoglobulin G4 in our cohort, suggesting that this laboratory profile is suboptimal for this population.

Women survive longer than men undergoing cytoreductive surgery and HIPEC for appendiceal cancer.

BACKGROUND: We hypothesize that women undergoing cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for peritoneal carcinomatosis from appendiceal cancer will have a survival advantage compared to men. METHODS: The National Cancer Database (NCDB) public user file (2004-2014) was used to select patients with PC undergoing CRS and HIPEC from appendiceal cancer. Univariate and multivariable analyses were performed. RESULTS: 1,190 patients with PC from appendiceal cancer underwent HIPEC and CRS. OS was significantly longer for women than for men, with mean and median OS being 73.8 months and 98.2 months for women vs 58.7 months and 82.5 months for men, respectively (p = 0.0032). On multivariable analysis, male sex (HR: 1.444, 95% CI: 1.141-1.827, p = 0.0022) and increasing age (HR: 1.017, 95% CI: 1.006-1.027, p = 0.0017) were both found to be independent risk factors for worse OS. CONCLUSION: Women undergoing CRS and HIPEC for PC from appendiceal origin live longer than men undergoing the same treatment. Increasing age was also found to be independent risk factors for worse survival.

Recurrence in Patients Achieving Pathological Complete Response After Neoadjuvant Treatment for Advanced Pancreatic Cancer.

OBJECTIVE: The aim of this study was to characterize the patterns and treatment of disease recurrence in patients achieving a pathological complete response (pCR) following neoadjuvant chemoradiation for advanced pancreatic ductal adenocarcinoma (PDAC). SUMMARY OF BACKGROUND DATA: A pCR is an independent predictor for improved survival in PDAC. However, disease recurrence is still observed in these patients. METHODS: Patients with advanced PDAC who were treated with neoadjuvant therapy and had a pCR were identified between 2009 and 2017. Overall survival (OS) was determined from the initiation of neoadjuvant, disease-free survival (DFS) from the date of surgery, and post-recurrence survival (PRS) from the date of recurrence. Factors associated with recurrence were analyzed using a Cox-regression model. RESULTS: Of 331 patients with borderline resectable or locally advanced PDAC, 30 achieved a pCR following neoadjuvant treatment and pancreatectomy. The median DFS for pCR patients was 29 months and OS 76 months. Recurrence was observed in 14 patients. No clinicopathologic or treatment characteristics were associated with survival. The median PRS following recurrence was 25 months. Treatment following recurrence included chemotherapy, radiation or ablation, and surgical resection. Hepatectomy or completion pancreatectomy was accomplished in 2 patients that remain alive 13 and 62 months, respectively, following metastasectomy. CONCLUSIONS: A pCR following neoadjuvant therapy in patients with advanced PDAC is associated with remarkable survival, although recurrence occurs in about half of patients. Nevertheless, patients with pCR and recurrence respond well to treatment and survival remains encouraging. Advanced molecular characterization and longitudinal liquid biopsy may offer additional assistance with understanding tumor biologic behavior after achieving a pCR.

Gastric cancer following pancreaticoduodenectomy: Experience from a high-volume center and review of existing literature.

BACKGROUND: Prolonged survival of patients after pancreaticoduodenectomy can be associated with late complications due to altered gastrointestinal anatomy. The incidence of gastric cancer is increasingly reported. We set out to examine our experience with gastric cancer as a late complication after pancreaticoduodenectomy with a focus on incidence, risk factors, and outcomes. METHODS: We queried our prospectively collected institutional database for patients that developed gastric cancer after pancreaticoduodenectomy and conducted a systematic review of the literature. RESULTS: Our database revealed 6 patients who developed gastric cancer following pancreaticoduodenectomy, presenting with a mean age of 62.2 years and an even sex distribution. All of those patients underwent pancreaticoduodenectomy for malignant indications with an average time to development of metachronous gastric cancer of 8.3 years. Four patients complained of gastrointestinal discomfort prior to diagnosis of secondary malignancy. All of these cancers were poorly differentiated and were discovered at an advanced T stage (≥ 3). Only half developed at the gastrointestinal anastomosis. Four underwent surgery with a curative intent, and 2 patients are currently alive (mean postgastrectomy survival = 25.5 months). In accordance with previous literature, biliopancreatic reflux from pancreaticoduodenectomy reconstruction, underlying genetic susceptibility, and adjuvant therapy may play a causative role in later development of gastric cancer. CONCLUSION: Long-term survivors after pancreaticoduodenectomy who develop nonspecific gastrointestinal complaints should be evaluated carefully for complications including gastric malignancy. This may serve as an opportunity to intervene on tumors that typically present at an advanced stage and with aggressive histology.

Patient-derived Organoid Pharmacotyping is a Clinically Tractable Strategy for Precision Medicine in Pancreatic Cancer.

OBJECTIVE: PDAC patients who undergo surgical resection and receive effective chemotherapy have the best chance of long-term survival. Unfortunately, we lack predictive biomarkers to guide optimal systemic treatment. Ex-vivo generation of PDO for pharmacotyping may serve as predictive biomarkers in PDAC. The goal of the current study was to demonstrate the clinical feasibility of a PDO-guided precision medicine framework of care. METHODS: PDO cultures were established from surgical specimens and endoscopic biopsies, expanded in Matrigel, and used for high-throughput drug testing (pharmacotyping). Efficacy of standard-of-care chemotherapeutics was assessed by measuring cell viability after drug exposure. RESULTS: A framework for rapid pharmacotyping of PDOs was established across a multi-institutional consortium of academic medical centers. Specimens obtained remotely and shipped to a central biorepository maintain viability and allowed generation of PDOs with 77% success. Early cultures maintain the clonal heterogeneity seen in PDAC with similar phenotypes (cystic-solid). Late cultures exhibit a dominant clone with a pharmacotyping profile similar to early passages. The biomass required for accurate pharmacotyping can be minimized by leveraging a high-throughput technology. Twenty-nine cultures were pharmacotyped to derive a population distribution of chemotherapeutic sensitivity at our center. Pharmacotyping rapidly-expanded PDOs was completed in a median of 48 (range 18-102) days. CONCLUSIONS: Rapid development of PDOs from patients undergoing surgery for PDAC is eminently feasible within the perioperative recovery period, enabling the potential for pharmacotyping to guide postoperative adjuvant chemotherapeutic selection. Studies validating PDOs as a promising predictive biomarker are ongoing.

A phase 2 study of GVAX colon vaccine with cyclophosphamide and pembrolizumab in patients with mismatch repair proficient advanced colorectal cancer.

BACKGROUND: Mismatch repair proficient (MMRp) colorectal cancer (CRC) has been refractory to single-agent programmed cell death protein 1 (PD1) inhibitor therapy. Colon GVAX is an allogeneic, whole-cell, granulocyte-macrophage colony-stimulating factor -secreting cellular immunotherapy that induces T-cell immunity against tumor-associated antigens and has previously been studied in combination with low-dose cyclophosphamide (Cy) to inhibit regulatory T cells. METHODS: We conducted a single-arm study of GVAX/Cy in combination with the PD1 inhibitor pembrolizumab in patients with advanced MMRp CRC. Patients received pembrolizumab plus Cy on day 1, GVAX on day 2, of a 21-day cycle. The primary endpoint was the objective response rate by Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. Secondary objectives included safety, overall survival, progression-free survival, changes in carcinoembryonic antigen (CEA) levels, and immune-related correlates. RESULTS: Seventeen patients were enrolled. There were no objective responses, and the disease control rate was 18% by RECIST 1.1. The median progression-free survival was 82 days (95% confidence interval [CI], 48-97 days) and the median overall survival was 213 days (95% CI 179-441 days). Biochemical responses (≥30% decline in CEA) were observed in 7/17 (41%) of patients. Grade ≥ 3 treatment-related adverse events were observed in two patients (hemolytic anemia and corneal transplant rejection). Paired pre- and on-treatment biopsy specimens showed increases in programmed death-ligand 1 expression and tumor necrosis in a subset of patients. CONCLUSIONS: GVAX/Cy plus pembrolizumab failed to meet its primary objective in MMRp CRC. Biochemical responses were observed in a subset of patients and have not previously been observed with pembrolizumab monotherapy in MMRp CRC, indicating that GVAX may modulate the antitumor immune response.

Blame it on the injury: Trauma is a risk factor for pancreatic fistula following distal pancreatectomy compared with elective resection.

BACKGROUND: Postoperative pancreatic fistula (POPF) remains a significant source of morbidity following distal pancreatectomy (DP). There is a lack of information regarding the impact of trauma on POPF rates when compared with elective resection. We hypothesize that trauma will be a significant risk factor for the development of POPF following DP. METHODS: A retrospective, single-institution review of all patients undergoing DP from 1999 to 2017 was performed. Outcomes were compared between patients undergoing DP for traumatic injury to those undergoing elective resection. Univariate and multivariable analyses were performed using SAS (version 9.4). RESULTS: Of the 372 patients who underwent DP during the study period, 298 met inclusion criteria: 38 DPs for trauma (TDP), 260 elective DPs (EDP). Clinically significant grade B or C POPFs occurred in 17 (44.7%) of 38 TDPs compared with 41 (15.8%) of 260 EDPs (p < 0.0001). On multivariable analysis, traumatic injury was found to be independently predictive of developing a grade B or C POPF (odds ratio, 4.3; 95% confidence interval, 2.10-8.89). Age, sex, and wound infection were highly correlated with traumatic etiology and therefore were not retained in the multivariable model. When analyzing risk factors for each group (trauma vs. elective) separately, we found that TDP patients who developed POPFs had less sutured closure of their duct, higher infectious complications, and longer hospital stays, while EDP patients that suffered POPFs were more likely to be male, younger in age, and at a greater risk for infectious complications. Lastly, in a subgroup analysis involving only patients with drains left postoperatively, trauma was an independent predictor of any grade of fistula (A, B, or C) compared with elective DP (odds ratio, 8.6; 95% confidence interval, 3.09-24.15), suggesting that traumatic injury is risk factor for pancreatic stump closure disruption following DP. CONCLUSION: To our knowledge, this study represents the largest cohort of patients comparing pancreatic leak rates in traumatic versus elective DP, and demonstrates that traumatic injury is an independent risk factor for developing an ISGPF grade B or C pancreatic fistula following DP. LEVEL OF EVIDENCE: Prognostic study, Therapeutic, level III.

A Qualitative Review of Neoadjuvant Chemotherapy in Resectable Pancreatic Adenocarcinoma.

The aim of this study was to evaluate outcomes of patients with resectable pancreatic adenocarcinoma (PDAC) who underwent neoadjuvant chemotherapy. The MEDLINE and PubMed databases were searched to identify relevant original articles investigating neoadjuvant therapy in resectable PDAC. Qualitative analyses were performed to investigate patient selection, disease stage, impact on perioperative outcomes, and cost-effectiveness. Forty-three studies met inclusion criteria for this review. Neoadjuvant chemotherapy for upfront resectable PDAC is cost-effective, safe, may result in lower stage disease and has potential survival advantages. With proper patient selection, neoadjuvant chemotherapy is an appropriate approach for upfront resectable PDAC. Nevertheless, the risk for disease progression and losing a curative surgical window highlights the need for appropriate patient identification, further discovery of superior biomarkers or molecular profiles representative of positive treatment response, and additional prospective comparative study.

Creation of Colonic Anastomosis in Mice.

Intestinal anastomoses are commonly performed in both elective and emergent operations. Even so, anastomotic leaks are a highly feared complications of colonic surgeries and can occur in up to 26% of surgical anastomoses, with mortality being up to 39% for patients with such a leak. Currently, there remains a paucity of data detailing the cellular mechanisms of anastomotic healing. Devising preventative strategies and treatment modalities for anastomotic leak could be greatly potentiated by a better understanding of appropriate anastomotic healing. A murine model is ideal as previous studies have shown that the murine anastomosis is the most clinically similar to the human case as compared with other animal models. We offer an easily reproducible murine model of colonic anastomosis in mice that will allow for further illustration of anastomotic healing.

Malnutrition, frailty, and sarcopenia in pancreatic cancer patients: assessments and interventions for the pancreatic surgeon.

The objective of this article is to review the available literature examining the impact of malnutrition, frailty, and sarcopenia on surgical morbidity among pancreatic cancer patients. We examine definitions used to diagnose and quantify these conditions and review the differences between them with regards to preoperative assessment and postoperative outcomes. The most relevant scoring systems are summarized. Lastly, we summarize current knowledge regarding effectiveness of specific interventions aimed at malnutrition, frailty, and sarcopenia for patients undergoing pancreatic cancer surgery.

Tobacco Smoking Associated With Increased Anastomotic Disruption Following Pancreaticoduodenectomy.

BACKGROUND: The effect of cigarette smoking on postoperative morbidity following pancreaticoduodenectomy (PD) for cancer is unclear. We hypothesize that smoking is associated with higher morbidity following PD. METHODS: A retrospective review of patients undergoing PD for cancer from 2010 to 2016 at a single institution was performed. Patients who had never smoked were compared to current or past-smokers with at least 1 pack-year history. Univariate and multivariable analyses were performed. RESULTS: Two hundred fifty-two patients met inclusion criteria. On univariate analysis, there was a significant difference between smokers and never-smokers in age at diagnosis (65.5 versus 68.6 y, P = 0.013) and fistula rate (28.5% versus 16.2%, P = 0.024). Male sex was significantly associated with fistula rate compared with female sex (15.5% versus 7.1%, P = 0.023). Comparing males and females separately, smoking correlated with higher fistula development only in the male cohort (22.5% versus 5.8%, P = 0.016 in men and 7.3% versus 9.1%, P = 1.00 in women). On multivariable analysis, current and past smoking was independently predictive of developing a fistula: odds ratio of 2.038 (P = 0.030). For current and past-smokers, male sex was an independent risk factor for developing a fistula: odds ratio 2.817 (P = 0.022). There were no other significant differences between groups in rates of postoperative complications. CONCLUSIONS: Smoking status is independently predictive of postoperative pancreatic fistula following PD for cancer. Among smokers, male sex is an independent risk factor for fistula. Further studies are needed to determine if smoking cessation before surgery decreases this risk, and if so, the optimal duration of cessation.